The present invention relates in general to a multi-slide wire and strip forming machine typically referred to in the trade as a universal four-slide wire and strip forming machine. More particularly, the invention pertains to an improvement in such a multi-slide machine so as to provide for improved efficiency in wire and strip forming.
In the universal four-slide machine each of the slides support tooling configured and adapted to provide for the forming of wire or strips. In connection with this forming there may be provided a shaping tool. Each of the slides is operated from a cam which in turn is supported from a camshaft A feed mechanism is also provided. In this connection in the prior machine of the assignee herein there are a pair of circular gears, referred to as change gears that provide for drive from one of the camshafts through the pair of gears to a feed mechanism. Normally these change gears are of equal diameter thus providing a 1 to 1 gear ratio This means that the shaft driving the feed mechanism rotates at the same rate as do the camshafts that operate the forming slides.
In the aforementioned arrangement the feed mechanism, also referred to as a feed slide moves forward advancing the wire or strip during 180.degree. of rotation, and returns during the remaining 180.degree. of rotation. The material whether it be wire or strip is gripped and fed during the forward 180.degree. stroke.
With this arrangement the change gears may be removed so as to provide a 90.degree. feed. In this case the change gears are in a ratio of 2 to 1 whereby the feed shaft rotates twice during each machine cycle. The feed gripper cam has only a 90.degree. dwell for the 90.degree. feed. Even though the feed slide makes two trips every cycle, the feed occurs only every other trip. This provides for 270.degree. of forming time. However, this arrangement cuts the production speed roughly in half.
Other four-slide machines also incorporate a 90.degree. feed systems but most of them accomplish it through the use of a complex cam arrangement. Also, such machines usually require additional linkages and are limited in production speed.
Accordingly, it is an object of the present invention to provide an improved multi-slide forming machine that is capable of operating at optimum production speed and which is furthermore capable of the construction of more complex wire and strip pieces by virtue of having an increased forming interval in comparison with the feed interval.
Another object of the present invention is to provide an improved multi-slide forming machine having improved flexibility of operation by virtue of providing control of the duration of respective forming and feeding intervals.
A further object of the present invention is to provide an improved multi-slide forming machine as in accordance with the preceding object and in which, for a single camshaft rotation, the forming time interval is greater than the feeding time interval, or alternatively, the feeding time interval is greater than the forming time interval.
Still a further object of the present invention is to provide an improved multi-slide forming machine that employs non-circular gear means intercoupling one of the machines camshafts with wire feeding means so as to provide a variable speed wire feed corresponding to constant speed rotation of the camshaft.
A further object of the present invention is to provide an improved multi-slide wire and strip forming machine that enables an increase in production speed even when constructing relatively complex piece configurations.